1. Field of the Invention
The present invention relates to a method for extending duration of a display apparatus having brightness compensation and an apparatus realizing the same, more particularly to, a method for extending duration of a display apparatus having brightness compensation and an apparatus realizing the same by properly dividing a non-volatile memory of the apparatus.
2. Description of the Prior Arts
For conventional display devices, such as FED, after being used for a while, the display will be getting darken in view of their brightness (also known as luminance) due to aging, and, since each pixel of the devices corresponds to a different period of brightness for difference colors, the aging level will differ. Hence, in order to maintain the brightness and the even color, the brightness of each pixel needs to be compensated individually.
Refer to FIG. 1A, which provides a display system 10, comprising a brightness compensation apparatus 101 which cooperates with a driver integrated circuit 102 so as to drive a display means 103, said compensation apparatus 101 further comprises: a volatile memory 104, for storing a brightness accumulation for each pixel in view of different color on the display means 103; a non-volatile memory 105, for preventing the brightness accumulating from missing from the system 10 during its shutting down period; and a calculating means 106, for accumulating the brightness of each pixel; wherein, as illustrated in FIG. 1B, a write-in area of the non-volatile memory 105 is evenly divided into n equivalent areas, such as area 0 to area n−1.
The usage record for brightness accumulation usage will be first stored by the faster volatile memory 104, then being sequentially forwarded to the driver IC 102. Since once if the system shutting down, these usage record will turn disappeared, so periodically, the record must be also stored in the non-volatile memory 105 so as the record can be refreshed in volatile memory 104 while the system regains operating.
FIG. 1C further illustrates the algorithm disclosed in the prior art. Supposed the needed accumulated brightness data is bit 0a˜bit 3a, and the data prior to accumulation is 31-bit data such as bit 0b˜bit 30b, then the data after accumulation is 31-bit data such as bit 0c˜bit 30c, and for the 31-bit data after accumulation, conventionally, only part of the maximum effect bits such as bit 15c˜bit 30c are stored in the non-volatile memory 105 so as to prevent data of said bit 0b˜bit 30b for the aforesaid volatile memory 104 from disappearance, which is illustrated in FIG. 1D.
However, in view of the non-volatile memory 105, the write-in sequence per unit capacity is limited, as a result, the conventional approach is using a higher capacity of the memory 105 to trade more write-in sequence, for example, if an eight time of write sequence is desired, then eight equivalent-sized flash memories each being divided into n equivalent areas are used to serve the write-in process in turn, as illustrated in FIG. 1B. Correspondingly, the higher-capacity flash memory will increase the system cost. Accordingly, in view of the above drawbacks, it is an imperative that an apparatus and method are designed so as to use the minimum capacity but achieve the same write-in sequence and meanwhile optimize the flash memory usage or duration as the foregoing.